EP0091173B1 - Verfahren zum Herstellen optischer Fasern - Google Patents

Verfahren zum Herstellen optischer Fasern Download PDF

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Publication number
EP0091173B1
EP0091173B1 EP83200469A EP83200469A EP0091173B1 EP 0091173 B1 EP0091173 B1 EP 0091173B1 EP 83200469 A EP83200469 A EP 83200469A EP 83200469 A EP83200469 A EP 83200469A EP 0091173 B1 EP0091173 B1 EP 0091173B1
Authority
EP
European Patent Office
Prior art keywords
tube
wall
passed
hydrogen
oxygen
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP83200469A
Other languages
German (de)
English (en)
French (fr)
Other versions
EP0091173A1 (de
Inventor
Cornelis Petrus Auwerda
Gerrit Jan Koel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Koninklijke Philips NV
Original Assignee
Philips Gloeilampenfabrieken NV
Koninklijke Philips Electronics NV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Philips Gloeilampenfabrieken NV, Koninklijke Philips Electronics NV filed Critical Philips Gloeilampenfabrieken NV
Priority to AT83200469T priority Critical patent/ATE14566T1/de
Publication of EP0091173A1 publication Critical patent/EP0091173A1/de
Application granted granted Critical
Publication of EP0091173B1 publication Critical patent/EP0091173B1/de
Expired legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C15/00—Surface treatment of glass, not in the form of fibres or filaments, by etching
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/012—Manufacture of preforms for drawing fibres or filaments
    • C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
    • C03B37/018—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
    • C03B37/01807—Reactant delivery systems, e.g. reactant deposition burners
    • C03B37/01815—Reactant deposition burners or deposition heating means
    • C03B37/01823—Plasma deposition burners or heating means
    • C03B37/0183—Plasma deposition burners or heating means for plasma within a tube substrate
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/012—Manufacture of preforms for drawing fibres or filaments
    • C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]
    • C03B37/018—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
    • C03B37/01876—Means for heating tubes or rods during or immediately prior to deposition, e.g. electric resistance heaters
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B2201/00—Type of glass produced
    • C03B2201/06—Doped silica-based glasses
    • C03B2201/08—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant
    • C03B2201/12—Doped silica-based glasses doped with boron or fluorine or other refractive index decreasing dopant doped with fluorine
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S65/00—Glass manufacturing
    • Y10S65/15—Nonoxygen containing chalogenides
    • Y10S65/16—Optical filament or fiber treatment with fluorine or incorporating fluorine in final product

Definitions

  • the invention relates to a method for producing optical fibers, in which the inner wall of a tube is etched with a fluorine compound and core glass is deposited on the etched inner wall from a gas phase by a chemical reaction, for the excitation of which a non-isothermal plasma is used, after which the tube collapses and is drawn into a fiber.
  • core glass is understood to be the glass that is deposited on the inner wall of the tube. This also means layers which are deposited from the gas phase and which can be referred to as adaptation layers and which as such do not belong to the core of the fiber in the optical sense.
  • the core of a fiber is to be understood as the part of the optical fiber in which the refractive index rises suddenly (stepped index) or gradually (gradient index) compared to that part of the fiber surrounding this part.
  • a chemical deposition process using a non-isothermal plasma is understood to mean a process in which a cold plasma is moved back and forth in a tube while oxygen and silicon tetrachloride are passed through the tube.
  • a dopant can be added to the gas mixture, which increases or decreases the refractive index of the deposited glass.
  • the gas pressure in the pipe is less than 150 mbar and is preferably between 1 and 30 mbar.
  • the glass tube is heated to a temperature between 1000 and 1200 ° C during the deposition. At this temperature, no thermal reaction occurs at the applied pressures, which could lead to glass soot formation in the gas phase. However, the heating prevents chlorine from being incorporated into the deposited glass layers. Built-in chlorine can cause gas bubbles to occur when collapsing and pulling fibers out of the preform formed during collapse. The heating during the deposition also prevents soot formation in the deposited layers during the collapse stage.
  • the object of the invention is to provide an etching process using a fluorine compound, whereby the laborious rinsing and drying can be avoided.
  • the inner wall of the tube is etched in that a hydrogen-free fluorine compound is passed through the tube and non-isothermal plasma is moved back and forth in the tube.
  • Suitable compounds for this purpose are, for example, F 2 , OF 2 and gaseous and liquid fluorine compounds to be brought into vapor form, such as CF 4 and C 2 F 6 .
  • Fluorocarbon compounds, preferably mixed with oxygen, are used to prevent free carbon from forming or polymerization from occurring.
  • the tube wall is etched, specifically with the formation of SiF 4 and possibly volatile fluorine compounds and impurities, which is located in or on the wall of the glass tube.
  • the drawing shows a diagram of a device for internally covering a tube 1, for example made of quartz glass, with a clear width of 6 mm, with layers of glass.
  • the tube 1 is in an oven 2.
  • a temperature of 1150 ° C. is maintained in the oven.
  • the glass layers are applied by passing a mixture of oxygen and SiCl 4 and the required dopant through the tube and moving a microwave resonator 3 back and forth along the tube.
  • a pressure of 25 mbar is maintained by a vacuum pump 4.
  • hexafluoroethane (C 2 F 6 ) is fed from a container 10 via a control device 6 and oxygen is fed from a container 11 via a control device 7 to a gas mixing device 5 and from there into the pipe.
  • the ratio C 2 F 6 : 0 2 is preferably at most 1: 2, so that the entire amount of carbon released can be converted at least into C0 2 .
  • the resonator is moved back and forth on the tube at a speed of 3 m / minute, while an electric field is coupled into the tube at a frequency of 2.45 GHz and with an energy of 200 W.
  • the pressure in the tube is kept at 25 mbar, but can also be higher in this phase, provided that the non-isothermal character of the plasma is not changed to isothermal. This is usually the case at a pressure above 150 mbar. Then there is a risk that powdery Si0 2 is formed in the gas phase via the reaction SiF 4 + O 2 . Under the influence of the plasma, fluorine ions are formed from the C 2 F 6 , which effectively etch the tube wall at the location of the plasma with the formation of SiF 4 . The SiF 4 formed is discharged via the pump 4 together with oxygen and possibly unconverted C 2 F 6 and C0 2 and possibly other gaseous reaction products.
  • the etching phase is preferably carried out during the heating of the furnace, which can take, for example, a quarter of an hour.
  • the passage of the fluorine compound is stopped and the deposition of the glass layers is started in the usual way.
  • oxygen is passed through a container 12 in which SiC1 4 is located and fed to the gas mixing device 5 via a control device 8, in which a mixture with oxygen and / or a dopant which is fed from a container 13 via a control device 9 to the mixing device is done as described, for example, in European Patent Application 0023066 and US Patent 4314833, the contents of which are considered, if necessary, to be included herein.
  • the tube is collapsed in the usual way and drawn out into an optical fiber.
  • the process according to the invention has the advantage that the etching takes place without hydrogen, so that there is no risk that hydrogen, for example in the form of hydroxyl (-OH) groups, will be absorbed in any way into the material of the tube wall.
  • Another advantage is that any mixture of suitable gases can be used.
  • etching can be started at room temperature while the etching can be continued until the tube is brought to the desired temperature for the deposition of the core glass material over the entire length. This results in a significant reduction in the production time, since the previous individual steps, rinsing with hydrogen fluoride solution, rinsing with water and drying, are avoided.
  • the tube interior is etched and polished in an extremely effective manner, which leads to a perfect quality of the optical fiber.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Manufacture, Treatment Of Glass Fibers (AREA)
  • Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
  • Surface Treatment Of Glass Fibres Or Filaments (AREA)
EP83200469A 1982-04-06 1983-04-05 Verfahren zum Herstellen optischer Fasern Expired EP0091173B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT83200469T ATE14566T1 (de) 1982-04-06 1983-04-05 Verfahren zum herstellen optischer fasern.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL8201453A NL8201453A (nl) 1982-04-06 1982-04-06 Werkwijze voor de vervaardiging van optische vezels.
NL8201453 1982-04-06

Publications (2)

Publication Number Publication Date
EP0091173A1 EP0091173A1 (de) 1983-10-12
EP0091173B1 true EP0091173B1 (de) 1985-07-31

Family

ID=19839538

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83200469A Expired EP0091173B1 (de) 1982-04-06 1983-04-05 Verfahren zum Herstellen optischer Fasern

Country Status (7)

Country Link
US (1) US4493721A (nl)
EP (1) EP0091173B1 (nl)
JP (1) JPS58190833A (nl)
AT (1) ATE14566T1 (nl)
CA (1) CA1208599A (nl)
DE (1) DE3360461D1 (nl)
NL (1) NL8201453A (nl)

Families Citing this family (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL8300650A (nl) * 1983-02-22 1984-09-17 Philips Nv Werkwijze voor het vervaardigen van een massieve voorvorm voor het trekken van optische vezels.
US4709986A (en) * 1984-06-18 1987-12-01 Polaroid Corporation Ensheathed optical fiber and coupling method
CA1263807A (en) * 1985-03-19 1989-12-12 Richard James Pilon Optical waveguide manufacture
US4610708A (en) * 1985-06-24 1986-09-09 Corning Glass Works Method for making metal halide optical fiber
US5188648A (en) * 1985-07-20 1993-02-23 U.S. Philips Corp. Method of manufacturing optical fibres
DE3528275A1 (de) * 1985-08-07 1987-02-19 Philips Patentverwaltung Verfahren und vorrichtung zum innenbeschichten von rohren
US4863501A (en) * 1985-09-26 1989-09-05 Polaroid Corporation, Patent Department Method of employing plasma for finishing start rods
US5069701A (en) * 1987-07-13 1991-12-03 Hughes Aircraft Company Preparation of fluoride glass by chemical vapor deposition
DE3731604A1 (de) * 1987-09-19 1989-03-30 Philips Patentverwaltung Verfahren zur herstellung einer monomode-lichtleitfaser
NL9100335A (nl) * 1991-02-26 1992-09-16 Philips Nv Werkwijze voor de vervaardiging van buisglas.
EP0598349B1 (en) * 1992-11-19 1998-07-29 Shin-Etsu Quartz Products Co., Ltd. Process for manufacturing a large sized quartz glass tube, a preform and an optical fiber
US5397372A (en) * 1993-11-30 1995-03-14 At&T Corp. MCVD method of making a low OH fiber preform with a hydrogen-free heat source
IT1267418B1 (it) * 1994-03-16 1997-02-05 Cselt Centro Studi Lab Telecom Procedimento per la realizzazione di fibre ottiche monomodo in vetro fluorurato.
FR2725712B1 (fr) * 1994-10-18 1996-12-13 Alcatel Fibres Optiques Procede d'amelioration geometrique d'un tube pour realisation de preforme
EP1325893B1 (en) * 2000-09-21 2016-11-23 Mitsubishi Cable Industries, Ltd. Method of manufacturing photonic crystal fiber
NL1020358C2 (nl) * 2002-04-10 2003-10-13 Draka Fibre Technology Bv Werkwijze en inrichting ter vervaardiging van optische voorvormen, alsmede de daarmee verkregen optische vezels.
NL1034059C2 (nl) * 2007-06-29 2008-12-30 Draka Comteq Bv Werkwijze voor het vervaardigen van een voorvorm voor optische vezels onder toepassing van een dampdepositieproces.
US8857372B2 (en) * 2007-12-10 2014-10-14 Ofs Fitel, Llc Method of fabricating optical fiber using an isothermal, low pressure plasma deposition technique
NL2004546C2 (nl) 2010-04-13 2011-10-17 Draka Comteq Bv Inwendig dampdepositieproces.
NL2004544C2 (nl) 2010-04-13 2011-10-17 Draka Comteq Bv Inwendig dampdepositieproces.
NL2004874C2 (nl) 2010-06-11 2011-12-19 Draka Comteq Bv Werkwijze voor het vervaardigen van een primaire voorvorm.
NL2009962C2 (en) 2012-12-11 2014-06-12 Draka Comteq Bv Method for activating an inner surface of a hollow glass substrate tube for the manufacturing of an optical fiber preform.
NL2011077C2 (en) * 2013-07-01 2015-01-05 Draka Comteq Bv A method for manufacturing a precursor for a primary preform for optical fibres by means of an internal plasma chemical vapour deposition (pcvd) process.
NL2015162B1 (en) * 2015-07-13 2017-02-01 Draka Comteq Bv Method for activating an inner surface of a substrate tube for the manufacturing of an optical fiber preform.

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3795557A (en) * 1972-05-12 1974-03-05 Lfe Corp Process and material for manufacturing semiconductor devices
DE2444100C3 (de) * 1974-09-14 1979-04-12 Philips Patentverwaltung Gmbh, 2000 Hamburg Verfahren zur Herstellung von innenbeschichteten Glasrohren zum Ziehen von Lichtleitfasern
DE2536456C2 (de) * 1975-08-16 1981-02-05 Heraeus Quarzschmelze Gmbh, 6450 Hanau Halbzeug für die Herstellung von Lichtleitfasern und Verfahren zur Herstellung des Halbzeugs
CA1029993A (en) * 1975-09-11 1978-04-25 Frederick D. King Optical fibre transmission line
JPS5510468A (en) * 1978-07-10 1980-01-24 Nippon Telegr & Teleph Corp <Ntt> Production of glass fiber for light communication
US4227975A (en) * 1979-01-29 1980-10-14 Bell Telephone Laboratories, Incorporated Selective plasma etching of dielectric masks in the presence of native oxides of group III-V compound semiconductors
DE2929166A1 (de) * 1979-07-19 1981-01-29 Philips Patentverwaltung Verfahren zur herstellung von lichtleitfasern
DE3000954C2 (de) * 1980-01-12 1982-04-22 Standard Elektrik Lorenz Ag, 7000 Stuttgart Verfahren zum Ätzen von Glasoberflächen, insbesondere bei der Glasfaser-Lichtleiter-Herstellung
GB2084988B (en) * 1980-10-02 1984-06-06 Post Office Methods of etching materials containing silicon

Also Published As

Publication number Publication date
JPH0239460B2 (nl) 1990-09-05
ATE14566T1 (de) 1985-08-15
CA1208599A (en) 1986-07-29
JPS58190833A (ja) 1983-11-07
NL8201453A (nl) 1983-11-01
US4493721A (en) 1985-01-15
EP0091173A1 (de) 1983-10-12
DE3360461D1 (en) 1985-09-05

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